Sectional slip.



W. G. KNAPP.

SECTIONAL SLIP.

APPLICATION FILED JAN. 9. I913.

Patented Jul 17, 1917.

WILLIAM a. KNAPP, or ALHAMBRA, CALIFORZNIA.

SECTIOINAL SLIP.

Application filed January 9, 1913. Serial'No. 741,109.

To all whom it may concern:

Be it known thatI, WILLIAM G. KNlAPP,

Y a citizen of the United States, residing at Alhambra, in the county ofLos Angeles and State of California, have invented new anduseful-Improvements in Sectional Slips, of

fwhich the following is a specification.

In oil well construction is-necessary to provide means for supportingthe casing of the well during the operation of drill ng the well. It isalso necessary at times during the drilling operation to raise and lowerthe casing. Ordinarily there is provided for this purpose a supportlngmember, commonly termed a. spider, which rests upon the floor of thederrick, or, where the derrick is provided with a cellar, upon the floorof the cellar. -.}.This' spider is provided with a central openingthrough which the cas ng extends vertically, and between the casing andthe wall of the central opening of the spider are provided a series ofsegments each having an inner gripping face adapted to engage the casingand a beveled outer face adapted to engage the wall of the opening inthe spider. The angle of the beveled 1nner face of the opening of thespider and the outer face of each slip has been determined by experienceto be about three inches to a foot. Should this angle be too great, theweight of the casing would cause the slips to back away from the caslng,thereby permitting the casing to slidedownwardly through the slips. Ifthe angle 1s made too small, the binding of the slips about the casingis. so great that the casing is plnched. When a great length of casingis supported by the usual form of slips, the slips become wedged sotightly in the spider that the casing when lifted, as is necessary attimes during the drilling operation, raises the slips and the spider. Itthen becomes necessary to use a sledge or other heavy object todisengage the spider and slips, which operation places a great strainupon the casing and lifting devices and causes liability of damage tosome portion of the mechanism.

One of the main objects of my invention is to provide slips made. insectional form which will immediately release upon raising the casing,without raising the spider or supporting n'iember.

Another object of my invention is to provide slips in which the casinggripping face may be made of maximumlength.

I Referring to the drawings, which are for illustrative purposes only:

ligure 1 1s a perspective View of a supporting member or spider providedwith slips embodying a form of my invention.

Fig. 2 is a sectional view on line-a2 m Fig. 1. f

Fig. 3 is a perspective view of one of the slips showing the casinggripping face thereof.

F1g.4 is a perspective view of one of the sllps showing the outer faceof the slip.

Fig. 5 is a diagrammatic view illustrating the manner of using thespider and slips for supporting the well casing.

My invention resides in general terms in producing an improved slip. ofsectional -form,'be1ng constructed of two or more parts, one of WhlCh'is an inner memberadapted: to engage the casing and another being anouter member having a tapered outer face adapted to engage the spider orsupporting member, the contacting faces of the two parts being taperedat "a greater angle' than the spider engaging face of the outer member.

l designates a supporting member or spider consisting of a heavy metal,casting having a circular body portion 2 provided with extensions orarms 3, each arm 3 being provided with a ring 4 which extends through anopening 5 in the respective arms, the rings a being provided tofacilitate the lifting or moving of the spider. The spider is providedwith a round central opening 6, the wall 7 of which tapers downwardlyand inwardly, as clearly illustrated in Fig. 2 of the drawing. .lVithi-nthe central opening 6 of the spider is arranged, in the form shown,three segmental sectional slips 10, each consistingof an inner or casinggripping mem ber 11 and an outer or spider gripping member 12. Theouter. face 13 of the spider gripping member 12 is beveled at the sameangle as the wall of the opening 6 in the spider. The angle shown, beingabout three inches to one foot, has been determined to Specification ofLetters Patent. P t t July m, 19.1%

ably g ater angle than the outer face 13 of the spi er gripping member-12. The inner face '14 of each member 12 is staggered, as indicated inFigs. 2and 3, and provlded -.with a shoulder 15. Each casing grippingmember 11- is of greater length than the re spective spider grippingmembers 12, be ng provided with an upper flange 17 whichrests upon theupper end of its associated outer member 12, and-a lower flange 16 whichextends under the lower end of the respective outer members 12, therebeing a space between the lower end of the mem-- bers 12 and therespective flanges 16 when the upper flange 17 is resting'upon the upperend of the respective outer members 12.

The casing gripping members 11 are each" -provided with anouterstaggered beveled face 18 of the same angle as the inner face ofthe members 12, the face 18 of each member 11 being provided with ashoulder 19, as clearly shown in Fig. 2, there being provided asufiicient distance between the shoulders 15 on the members 12 andshoulders 19 on the members 11 so that the same at no time come intocontact with each other. In each flange 17 of the respective innermembers 11 is provided an opening 20 throughwhich downwardly extends thethreaded end 21 of an eye 22, the threaded end 21- extending into thespider gripping member 12 of the respective slips. The lower flange 16ofeach inner member 11 is provided with an opening 23 through whichextends a pin 24, the inner end of which is threaded into the lower endof the respective outer members 12. The eyes 22 and pins 24 serve tokeep the two parts of each slip, namely, the casing gripping member 11and the spider gripping member. 12,.' in proper relation to each other.'Each easing gripping member 11 is provided with a series of circularteeth 26, the pointsof which are extended upwardly and cut at intervals,as indicated at 27, thereby providing a plurality of teeth ries ofcorners or edges '30, thereby adding additional length of life to thegripping action of the slips, the cuts 27 being preferably arranged instaggered form, as indicated in Figs. 2 and 3.

The device is used in the following manner:

As illustrated in Fig. 5' the spider 1 is placed upon the floor of thederrick indicated at 40, the casing 41 extending through the spider asshown with the slips 10 within the central opening 6 ofthe spiderbetween the same and the casing 41. The weight 41 is lowered theoperators take hold of the eye bolts 22 and pull the outer or spider.

g pping members 12 upwardly until they are in substantially the positionshown in Fig. 2, the inner members 11 resting loosely by means of theirflanges 17 upon the top of the members 12. The operators hold themembers 11 and 12 in the same relative position as the casing islowered. This lowering of the casing causes the teeth 26 to grip thecasing and the members 11 and 12 are carried down together and wedged inthe spider 1 gripping the casing firmly at the same time. There is nomovement of the inner member 11 with relation to the outer member 12,the two members moving downwardly with the casing, the only slidingmovement being on the-beveled face 13.

,It is a well known fact that when metal surfaces are ground togetherunder heavy pressure they tend to becomewelded together due probably toa locking action of the surfaces. This action is known in mechanics asseizing. In the ordinary form of slip having a single wedge this seizingtends to freeze the wedge to the spider and makes the removal thereofvery diflicult. It is to obviate this difficulty which is oftenv soserious as to call for vigorous action with asledge hammer that theslips 10 are made in two parts 11 and 12. There being no sliding betweenthese members but merely an expansive action they do not seize but partreadily and cleanly. Moreover the wedging angle between the members 11and 12 being greater than the angle of the surface 13 the tendency tostick is greatly reduced.

\Vhen it is desired to raise the casing, any of the ordinary or wellknown forms of elevating means may be employed, and as the casing movesupwardly the outer face 18 of each inner member 11 immediately becomesdisengaged from the inner face 14 of each outer member 12, due to thegreat angle of the respective adjacent bearing faces which immediatelypermits an expanding action of the inner members 11. The inner members11 thereupon drop away .or become disengaged from the casing.

Should the weight of the casing have caused the teeth of the innermembers 11 to enter the casing, thereby causing the inner men bers 11 toremain in engagement with the casing after the outer bearing face ofeach bearing faces of the inner and outer memb'ers l1 and 12respectively, the striking of the flange 16 against the lower end of therespective outer members 11 would cause disengagement of the outermembers 12 and the spider, and at the same time cause disengagemen-t ofthe inner members 11 with the attached 'to the rings 4 shown onthespider.

What I claim is: 1. A casing support comprising a supporting memberhaving a beveled opening therein, a series of segmental slips in saidopening, each consisting of relatively movable inner and outer members,a flange on each inner member at the upper end thereof extending overthe upper'end of its associated outer member, and a flange on each innermember at the lower end thereof ex tending under the lower end of itsasso-' ciated outer member, said flanges being adapted to alternatelyengagethe opposite the outer face of the .outer member, and a ends ofsaid outer members. 4

2. A sectional slip of segmental form comprising an inner member,an'outer member connected to said inner'member to permit relativemovement therebetween, said outer member having an outer beveled face,said members having slidably engaging faces bev- 1 eled at ananglegreater than the angle of I flange on the inner member adapted to engagethe top of the outer member.

3. A sectional slip of segmental form comprising an inner member, anouter member connected to. said inner member to ermit relative movementtherebetween, sai outer member having an outer beveled face, saidmembers having slidably engaging faces beve eled at an angle greaterthan the angle of the outer face of the outer member, a flange 0n theinner member adapted to engage the top of the outer member, and a flangeon the inner member adapted to engage the lower end of the outer member,said flanges being arranged to alternately engage the opposite ends ofsaid outer member.

4. A sectional slip comprising an outer member having an outer beveledface and a stepped inner face beveled at an" angle greater than theouter face, an inner member having a toothed inner face and a steppedouter face corresponding to the inner face of the outer member, a flangeextending outwardly from both ends of the innermemb'er over therespective ends of'the outer member, said flanges being adapted toalternately engage the opposite ends of the outer member, and an eyebolt secured to the up per end of the outer member extending through anopening in the inner member.

5. A casin support comprising a supporting member having a beveledopening therein, support gripping members placed therein, 'means wherebysaid'support grippin members may be supported independent y of saidsupporting member, casing. gripping members between said supportgripping members and the casing, and means by which said casing grippingmem bers may be supported on said support grip-' ping members.

6. A casing support comprising a supporting member having a beveledopening therein through which the casing passes, wedge shaped supportgripping members placed in said opening, means by which the opening,casing gripping members between said support gripping members and thecasing, means whereby said support gripping members may be supported outof contact with the conical surface of said conical opening in saidsupporting member, and flanges V on said casing gripping membersadaptedto limit the downward movement of said casing gripping members withrelation to the 4 support gripping members.

8. A casing support comprising a supporting member having a beveledopening therein through which the casing passes; 4

outer wedges in this opening, inner wedges between the outerwedges andthe casing, means whereby said outer wedgesmaybe supported out ofcontact with the walls of said beveled opening, and means formed on theinner wedges whereby said inner wedges may be-suported on the outerwedges.

9. A casing support comprising a supporting member having a beveledopening through which the casing passes, outer wedges in this opening,inner wedges in this opening, and eye bolts secured in the top of saidouter wedges by means of which the weight of the outer wedges may besupported independent of the supporting member.

10. A casing-supportcomprising a sup-- porting member having a beveledopening through which the casing .passes, outer wedges in this opening,inner wedges'in this opening, flanges on said inner wedges projectingout over the outer wedges, and means on said outer wedges whereby theweight of said outer wedges may be, supported from above independent ofthe sup- 'which are independent of. said supporting porting member.

f 11. A casing support comprising a supporting member having a beveledopening through which the casing passes, outer wedges in this opening,inner wedges in this opening, flanges on said inner wedges projectingout over the outer wedges, and eye bolts fixed in the top of said outerwedges by means of which the weight of said wedges may be supportedindependent of the sup porting member. W p

12. A casing support comprising a supportingmember having a beveledopening through which the casing passes, outer wedges in this. opening,inner' wedges in this opening, flanges on said.inner:wedges projectingout overthe outer wedges flanges on said inner members projectingbeneath 'the outer members, and means on said outer wedges for attachingsupporting means member.

.13. A casing support comprising a supporting member having a beveledopening through which the casing passes, outer wedges in this opening,inner wedges in this opening, flanges on said inner wedges projectingout over the outer wedges, flanges on said inner members projectingbeneath the outer members, and eye bolts on said outer wedges to whichindependent supporting means may be attached.

14. A sectional slip adapted to be used between a cylindrical casing anda conical hole in a supporting member said sli comprising an outermember, means w ereby' said outer member may be supported independentlyof said casing or said support, an inner member, and means formed on theouter member for supporting said inner 'member.

In testimony whereof, I have hereunto set my hand at Los Angeles,California, this th day of December, 1912. V

WILLIAM G. KNAPP. In presence of FRANK L. A. GRAHAM,

LORRAINE E. Dmmow.

